Days Between Dates Calculator 📅
Find exact days, business days, weeks, months & years between any two dates. Includes age difference, Excel formulas, and countdown. Free, instant, no login.
Days Between Dates Calculator — Calculate Date Difference Online
Our free days between dates calculator finds the exact number of calendar days, business days (weekdays only), weekend days, weeks, months, hours, and years between any two dates — instantly and accurately, with full leap year support. Whether you are calculating the number of days between two dates in Excel and need a quick reference, counting down to a wedding or graduation, measuring how long a project has been running, or calculating an age difference between two dates, this tool gives you a complete breakdown in seconds.
Excel Formula for Calculating Number of Days Between Two Dates
If you want to calculate the number of days between two dates in Excel, there are several formulas depending on what you need. The simplest method for total calendar days is =B2-A2 (where A2 is the start date and B2 is the end date) — format the result cell as a number, not a date. For business days only (excluding weekends), use =NETWORKDAYS(A2, B2). For a complete years-months-days breakdown, Excel's DATEDIF function works: =DATEDIF(A2, B2, "Y") for complete years, =DATEDIF(A2, B2, "YM") for remaining months, and =DATEDIF(A2, B2, "MD") for remaining days. The DAYS function is another option: =DAYS(B2, A2) returns the number of days from A2 to B2. This calculator displays all these Excel formulas with your specific dates pre-filled so you can copy and paste directly into your spreadsheet.
Calculate Age Difference Between Two Dates
The age difference calculator function shows the exact time elapsed between two dates in years, months, and days — the same format used to express someone's precise age. Enter any two birthdates to find the age gap between two people, or enter a birthdate and today to find someone's exact current age. For example, from March 15, 1990 to July 20, 2026 is exactly 36 years, 4 months, and 5 days. This is more precise than simply subtracting birth years, and it correctly handles month-end and leap year edge cases that simple subtraction gets wrong.
Calculate Business Days Between Two Dates
Business days (also called working days or weekdays) are Monday through Friday only, excluding Saturday and Sunday. This matters for project planning, SLA calculations, invoice payment terms (e.g. "Net 30 business days"), shipping estimates, and legal deadlines where "10 business days" means something different from "10 calendar days." This calculator counts business days precisely by iterating through each date and checking the day of the week — the same method Excel's NETWORKDAYS function uses. Note that this calculator does not exclude public holidays, as holidays vary by country and organization.
Common Use Cases — When Do You Need to Count Days Between Dates?
- Project management: How many calendar and working days remain until a project deadline?
- Event countdowns: Days until a wedding, birthday, graduation, vacation, or product launch.
- Legal and financial: Contract payment terms, statute of limitations, notice periods, probationary periods.
- Medical: Days since a surgery, days into a medication course, pregnancy weeks and days.
- HR and payroll: Employee tenure, probation periods, notice period calculations.
- Age calculation: Exact age in years, months, and days for passports, insurance, and medical forms.
- Relationship milestones: Days together, anniversary countdowns, "how long ago was our first date."
What Makes This Calculator Different?
Most free date difference tools show just total days. This calculator adds business days, weekend day count, total hours, an exact years-months-days breakdown, quick date buttons (+7, +30, +90 days), a date swap button, pre-filled Excel formulas with your dates ready to paste into spreadsheets, and a copy results button. All calculations run in your browser with no server calls, and leap years are handled correctly in all calculations.
Frequently Asked Questions
How do I calculate the number of days between two dates?
Select your start and end dates above. The calculator subtracts the earlier from the later date and shows total calendar days, business days, weeks, months, and a full years-months-days breakdown instantly.
What is the Excel formula for calculating number of days between two dates?
=B2-A2 for calendar days, =DAYS(B2,A2) as alternative, =NETWORKDAYS(A2,B2) for business days. For years/months/days: =DATEDIF(A2,B2,"Y"), =DATEDIF(A2,B2,"YM"), =DATEDIF(A2,B2,"MD"). This calculator shows these formulas with your dates pre-filled.
How do I calculate age difference between two dates?
Enter the earlier date as start and the later as end. The Exact Date Difference section shows the age gap in years, months, and days — correctly handling month-end and leap year edge cases.
How do I calculate business days between two dates?
The Business Days stat excludes Saturdays and Sundays. In Excel, use =NETWORKDAYS(A2,B2). Note this calculator does not exclude public holidays, which vary by country.
How many days are in a year including leap years?
365 days normally, 366 in a leap year (divisible by 4, except century years must be divisible by 400). This calculator accounts for leap years in all calculations automatically.
How do I count down days to a future date?
Set today as start date and your future event as end date. The calculator shows days, business days, weeks, and months remaining. Use the +7/+30/+90 day buttons for quick countdowns.
About This Tool
This Days Between Dates Calculator was built by the FreeImageTools team — project managers, HR professionals, and developers who calculate date differences daily for deadlines, contracts, and planning. The original tool showed only 3 values. We rebuilt it to show total days, business days, weekend days, weeks (with remainder), months, years, total hours, an exact years-months-days breakdown, direction label (past/future), quick set buttons, a swap button, Excel formula reference with dates pre-filled, and a copy results button. All calculations run in the browser with full leap year accuracy. Reviewed in July 2026.